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A Roman nose is cool |
What’s wrong with a Roman nose? The current Australian Alpaca Association (AAA) Breed Standard lists the Roman nose as a fault, and the AAA Male Certification Regulation and the AAA Screening Regulation (import standard) as a disqualifying defect.
It
is true that short faces appeal to us. This is an instinctive response, which
triggers maternal feelings towards any animal with a baby-shaped head (short
face and exaggerated forehead). This is probably why so many domestic animals
have been developed to have short faces. This is found in dogs, pigs, cattle,
cats, and birds. There is a tendency in the alpaca industry to favour short
faces as well. Many Peruvian alpacas exhibit this attribute.
It
should however be borne in mind that the nose is not only used to inhale and exhale
air, but is also an important organ for thermoregulation.
The
figure below illustrates the importance of an anatomical structure, found in
Ruminants, Camelids and Carnivores, but not in Primates, for the regulation of
cerebral temperature. This structure is called rete mirabile (admirable
network).
After: RUCKEBUSCH Y. –
Physiologie, Pharmacologie, Thérapeutique animales, 2nd Edition –
Maloine S.A. Paris, 1981, p186
Indeed
it is an admirable setup: Venous blood coming back from the nose is colder than
arterial blood, because it has been cooled down within the nose, by exposure to
air. When coming back up the nose, towards the brain, it is collected in the
cavernous sinus, and cools down the arterial blood within the rete mirabile.
The arterial blood in the rete mirabile is actually on its way to the
brain via the circle of Willis. Therefore, in species equipped with this
device, the temperature of the brain can be lower than that of the rest of the
body. This is not possible in Primates. The longer the nose, the better the
cooling effect. Many mammals living in very hot climates exhibit a very long
nose indeed. This is the case in many species of antelopes.
As
we are trying to adapt our alpacas to our harsh Australian climate, it seems
therefore surprising that some breeders would select for shorter and shorter
noses in alpacas. We want our animals to be healthy and able to fend by
themselves under extensive farming conditions. None of the breeds of sheep used
for wool production in Australia has a short nose. The Merino is a perfect
example of a classic Roman nose. Let’s learn from our fellow farmers and keep
the beautiful Roman profile on our alpacas. It not only looks good, it is a
necessity!
Our
suris will be selected to maintain this attribute.
Pierre Baychelier